This course examines watershed approaches to maintenance of the hydrological, chemical, and biological integrity of the nation's waters. Water supply topics include rainfall runoff relationships, probabilistic flow analysis, multiple-objective reservoir siting and operation, and safe yield analysis. Water quality topics include regulatory requirements; non-point source runoff; point source discharge; water quality analysis of streams, lakes, and estuaries (including waste heat, conventional pollutants, and toxic chemicals); and in-stream biological resource requirements and assessment. Both the water supply and water quality discussions provide an overview of current computer simulation models. The course concludes with new integrated approaches for watershed management, including Waste Load Allocation and Total Maximum Daily Loss (TMDL) analysis for pollutants entering water bodies.